1. Field of the Invention
The present invention concerns a development of the three-way diaphragm valve described in WO 95/00782.
2. Description of the Background Art
That diaphragm valve is intended for controlling a flow of gaseous or liquid fluid and includes a valve housing having a valve chamber. Into the valve chamber opens a central channel and on each side thereof a first side channel and a second side channel, respectively. Valve seat means is arranged in the housing and an elastic diaphragm is adapted to be brought into and away from sealing contact with at least one of the valve seat means by means of control means for actuating the diaphragm. At least one portion of each valve seat means is common to the central channel and one of the side channels. Two control means are arranged to press the diaphragm against one such portion each, thereby to shut passage of fluid between the central channel and the respective side channel. The two control means also raise one portion each of the diaphragm off the respective portion of the valve seat means thereby to open passage of flow between the control channel and the respective side channel.